1. Technical Field
The present invention relates to a robot control device, a robot, and a simulation device.
2. Related Art
Researches and developments of a technique for virtually simulating the operation of a robot control device that controls a robot have been performed.
Concerning the technique, there has been known a robot simulation device that moves a virtual robot along a track, the robot simulation device performing, at an interrupt interval, a track calculation process for calculating a track after a sampling time of the virtual robot and individually changing both of the sampling time and the interrupt interval in a range in which the sampling time is equal to or shorter than the interrupt interval (see, for example, JP-A-2012-135821 (Patent Literature 1)).
There has been known a robot including a base and a manipulator including a plurality of arms (links). One arm of two arms adjacent to each other of the manipulator is turnably coupled to the other arm via a joint section. An arm on the most proximal end side (on the most upstream side) is turnably coupled to the base via a joint section. The joint sections are driven by motors. The arms turn according to the driving of the joint sections. For example, a hand is detachably attached to an arm on the most distal end side (on the most downstream side) as an end effector. For example, the robot grips a target object with the hand, moves the target object to a predetermined place, and performs predetermined work such as assembly.
As a robot control device that controls the operation of such a robot, there has been disclosed a device that defines a virtual safety fence set on the inner side of a real safety fence and two or more three-dimensional space regions set to include a wrist of the robot and, work, a tool, or the like included in the wrist and controls the robot (see, for example, JP-A-2004-322244 (Patent Literature 2)).
The robot control device collates predicted positions on track calculation in the three-dimensional space regions and the virtual safety fence and, when any one of the three-dimensional space regions intrudes into the virtual safety fence, stops the operation of the robot. Consequently, it is possible to suppress collision of the robot and the real safety fence.
However, in the robot simulation device described in Patent Literature 1, the interrupt interval sometimes changes according to other interrupt processing. As a result, a shift sometimes occurs between time when the robot simulation device causes the robot to perform predetermined work and time when a real robot control device causes a real robot to perform the work.
In the robot control device described in Patent Literature 2, even if stop operation of the robot is started when the three-dimensional space region intrudes into the virtual space fence, for example, when the operating speed of the robot is high, it is likely that the robot cannot instantaneously stop and collides with the safety fence.